1,3,7-triazabicyclo [3.3.0] octanes



Patented Jan. 29, 19.46

{153;7-TRl'AZfiBICYCLO [3.3.0] OCTANES 'Mur'ray "SenkusfTerre Haute, Ind, assignor 'to Commercial Solvents-Qorporation, TerreHaute,

'Ind., a corporation of Maryland N Drawing. Application Febi'uary '28, 1944,

Serial No. 524,285

* i'z oiaims. (015260-309) My invention 're1ates-to;anew class of chemi- -cal compounds and to'a process for preparing the same. More particularly-it relates to 1,3,7- triazabicyelo [3.3.0] octanes' havingathe following general structural formula:

wherein R represents hydrogen, alkyl, aryl, cycloaliphatic or heterocyclic'; '-"R "maybe either hydrogenfalkyl, aryl, heterocyclic,"cycloaliphatic, or "afalkyl; and R "maybe hydrogen,'alkyl,"'aryl, aralkyl orhetero'cy'clic. v V

"Typical compounds "included by the above "generic formula are methyl#3,7 diisopropyl- 1-:j3,7-triazabicyclo [3.3.0] octane, 5e'ph'enyl l3fi- 'dioyclohexyl 1;3,7- triazabicyclo 3.3.01 'octanef'5- methyl 3,7 -'diisopropyl 2;8 -bis(' 1 -ethy1pentyl) "1,3,7-triazabicyc'lo 3.3101 octane, "5 ethyl-3j7-di- 'benzyl- 2,8 'diphenyl 1,37-triazabicyclo [3.3.0] octane, 5 methyl-3,7-diisopropyl 28 difurfuryl- 1',3,7-triazabicyclo [3;3.0 octane, fi cyclohexyl- 3,?*--ditetrahydrofurfuryl 1,3,7 trlazabicyclo [3.3.0] octane, 5-methyl-3,7-dipl'ienyl 1,3,7 triazabicyclo [3.3.0] octane, 5 methyl -3fl-diisopropyl 2,8 diphenyl 1,3,7-triazabicyc1o' [33.0] octane, and the like.

Reactions between carbonyl and polyamino compounds are well known, however, all of such reactionsvof which I am aware,.prior-to the present invention, have yielded 'only polymeric mate'- rials. I have now discovered that a -new class of chemical compounds; to-wit, 1,3,7-triazabicyclo -[3.3.0] octanescan be synthesized by reacting an aldehyde with a triam-inehaving thev three-amino groups attached to adjacent carbon-atoms.

In preparing such compounds, it is generally preferable-to react the aldehyde with a suitable 'triamine in a 1 ratio; of two moles of aldehyde to one of-triam-ine. Also, it 'isdesirable' to'employ --a water-immiscibl liquid such as toluen'e, benzene, -xylene or theirequivalent =as a solvent for the reaction and toassistinatheiremoval-of water :produced by the -reacti'on. During "the formation of the 1,3,7'-triazabicyclo-[3.3.01 octane, water is observed to collectrather rapidly in the distillate, however, when the'rate of water formation-decreases such is an indication that there- "action is substantially complete. 'The solvent-- and other more volatile impurities present are then 'distilled ofi atatniospheric pressure and theresidue; "if liquid, is subjected to' further fractionation purified by irecrystallization frombenzene,petro- -leum ether, 1 or similar solvents.

The procedure as above described is subiect to several modifications :and in certain instances such variations are "highly :desirable. :Fo'r example,:if an' aldehydeis employed that isisubstantially insoluble in'water an excess'can be advantageouslyusedas: a meansfo'r-removin'g' thewa'ter produced 'by the condensation f of triamine with the aldehyde. large excess'of the latt'er' is not necessary f'sinceit can be continuously separated from the distillate and-returned to :the reaction hiixtiire. Another advantage of dosing the-aldehyde in amounts'which' exceed combining proportionsresides in theifactthat the reaction involved is reversible and the presence of an' excess of aldehyde tends to iclrive the reaction to completion in' the desired direction. Frequently, when a relatively high boiling aldehyde is' used, it is desirable to add to the'reaction' mixture? from 25 to of benzene, toluene, or similar substance, based on' the excess of aldehyde resent, in order to: reduceth'e' boiling point of the reaction mixture to a temperature "that does not deleteriously afiect the= formation of: the desired- 153;?- triazabicycl'o [333.0] octane.

The triamines employed in carrying out my invention 'c'onstitute a 'Wide range of compounds and may'ib'erepresented by the following 'generic for'mula in' which the substituent R maybe either :alkyl, aryl, hydrogen, or cycloaliphatic; and R represents hydrogen, alkyl, cycloaliphatic, 'aryl, aralkyl or "het'erocycli'c: 1

v -R HNoHr-' J-oH,NHR

ypical examplemr triamines includefby' the "above *formula are '1f2i3 13ro'p'anetriamine, "2- amino 2-methyl 113#propanebisphenylamine, 5- aniino-'-2,5j8-trimethyl-3,7-diazanonane, 5-an'ii'no- 5-phenyl-2,8-dimethyl-3,7 diazanonane, 2 amino-2-methyl- -1,3 propanebiscyclohexylamine, 2-- "amino '2 ethyl-1,3-propanebisfurfurylarn'ine, 2- 'amino '2 -"c'yclohexyl -1',3 picrianebistetraihy'dxofurfurylamine, 2 -"phen'yl-'1,2,3 propanetriamine, and the like. 'Triamines containing three primary aminolgroups may be synthesized by reacting liquid ammonia'with the required 1,2,3- trihaloalkane under pressure in a known manner. Triamineshavin'g" a primary amino groupbnthe central carbonjatomand secondary aminogroups "on either side" thereof "are "preferably synthesized in accordance with the procedure described in my 5 copending application, UnSfiSerial 'No. 455,932

-Vunder reduced pressdre. The l;3l'l trlazablcyclo H filed-August 24,11942. By the procedure there de- -'scribed, the "desired nitro amine is subjected to liquid phase hydrogenation inthe" presence6f a suitable "hydrogenation i'catalystsuch as, for :examplej-Raney'nickel. K'solvntsuchds methanol formaldehyde,94= g. of -amino-2,5,8-trim 3,7-diazanonane having the structure or ethanol is preferably employed. Hydrogenation ofithenitroamine is effected at. pressuresjn the neighborhood of 500 lbs. per square inch and at temperatures of about 35 C. After h'yd'ro'gen adsorption is complete, the triamine can be iso-.

lated from the reduction mixture in a known manner. f The nitroarnine employed as a starting. ma-

terial for the preparation of such, triamines may be synthesized in accordance with the procedure 2,393,826 i 86.0-86.5 (3 mm), in a'conversion of 82% of,

.theory. 7, This compound was a..c,olorless mobile liquid and possessed a faint pyridine-like odor.

described in my copending application-U. S. Se-

rial No. 482,756 filed April 12, 1943. By this procedure, a primary aliphatic amine is reacted with formaldehyde to form the corresponding lSI-hydroxymethyl monoalkylamine which is in turn reacted with an equimolecular quantity ofa primary nitroparaflin to produce the'desired nitroamine; V I

An excepti'on'to the procedure described'immediately above is encountered in instances where primary nitroparafins.

scribed in co-pending application, U. S. Serial No. 473,523 filed January 25,1943, by Harold G. Johnson; By this procedure, a primary aromatic amineis reacted with a suitable dihydric primary nitro alcohol in the presence of a, basic catalyst such as, for example, sodium hydroxide, tributylamine, triethylamine, trimethylbenzylaminonium ''hydroxide, or thelike, at a temperature-of approximately 50 C. I The nitroaminethus produced can then be subjected to hydrogenation, in accordance. with the general procedure outlined As examples of aldehydes that may be employed in carryingout my invention, there may be mentioned formaldehyde, butyraldehyde, isobutyraldehyde, Z-ethylhexaldehyde, benzaldehyde, phenylacetaldehyde, p -tolualdehyde, furfural, and the like. i

The examples which follow are illustrative of the various types of 1,3,7-triazabicyclo [3.3.0] octanes that come within the scope of my invention. 7 They are likewise illustrative of the procedure whereby these new chemical compounds may be synthesized. However, it is to be specifically understood that such examples in no way limit the scope of my invention with respect to either the product or process demonstrated therein, since I t have found that the reaction involved is very general-in character and will occur under the conditions set forth when reacting substantially any triamine of the class described with an aldehyde of the various types enumerated above.

Example I A mixture consisting of'75 ml. of.36% aqueous ethyland 200. m1. of benzene was refluxedin aflask connected to a suitable condenser and moisture trap. After water ceased to separate in the moisture trap, the residue was distilled through an efficient fractionating column at atmospheric It was'solubie 'inacetone, methanol, benzene, ethyl'ether, and petroleum ether. It dissolved in water with considerable evolution of heat. 1.3;Analysis: Calculated for C12H25N32 N, 19.90.

Found: 19.76. n ,1.4662;

, Example II 5 methyl 3,7 diphenyl 1,3,7 triazabicyclo [3.3.0] octane was prepared by gently distilling a 7 mixture consisting of 265g. of 2-amino-2-methit is desired to synthesize triamines of the above general type from primary aromatic amines and The procedure prefer- .ably employed in the-latter case is suitablyde yl-N,N-diphenyl-LB-propanediamine, 14 ml. of 36% aqueous formaldehyde,- and 100 ml. of benzene until the removal of water from the reaction mixture substantially "ceased. The residue thus obtained was placed on a steam bath and the benzene removed therefrom under reduced pressure. The product in the reaction vessel was a solid and amounted to 31 g. This crude 5-meth- -yl-3,7-diphenyl-1,3,7-triazabicyclo [3.3.0] octane was next recrystallized from .100 ml. of cyclo-. hexane. A white crystalline product amounting methanol. The 5-methyl-3,7-di-isopropyl- 2,8 diphenyl-1,3,7 triazabicyclo [3.3.0] octane thus produced amounted to 176 g. Thisproduot was further purified by'rec'rystallizingonce from 150 ml.

of benzene giving 73 g. or a white crystalline I product. melting at C Analysis; Calculated I for C24H33N3i N, 1 1.57. Found: N, 11.47. V

V I EwahzpleIV A mixture consisting of 35s. or 5-am ino 2,5, 8-

trimethyl 3,7-diazanonane, and, Lethylhexalde- -hyde -in an amount corresponding to approximately 100% excess of that theoretically required 'to'- completely combine with the aforesaid tripressure until the major portion of the benzene w had been removed. Further rectification-was th'en carried out under reduced pressure and as a result there was obtained 5-methyl-3,7-diisopropyl-1,3,7-triazabicyclo 3.3.0] octane, boiling at amine, was heated to'reflux temperature andthe water formed during the condensation removed with the- 2 ethylhexaldehyde as a constant-boiL ing mixture. Whenobservable amounts of water ceased to come overinto the distillate; the residue was distilled under vacuum to remove theexcess .2-ethylhexaldehydea'nd the desired 5 -methyl vzabicyclol3.3.0] octane boiling at 173 C. (0.9.

'mm.):-was collected- 'The liquid product thus obtained amounted to 33 g. I a e 1 Analysis: Calculated for ,C'26H53N3: N, 10.3. Foundz' N, 10.10. n5 1.4726; e

I T V V 1 ,38, 0-8903 The 1,3,7-triazabicyclo [3.3.0] octanes 'ofmy invention will be-found useful in the synthesis of numerous'v novel and. valuable compounds. Other uses of these new materials will readily occur to those skilled in the art. Likewise, it'will be apparentto those familiar with the art to which the present invention isdirected, that the Calculated for C'1cH21N3: N, 15.05. t

scribed, and removing the water produced by a procedure for the preparation of thel,3,7-triazabicyclo [3.3.0] octanes as described above may be modified in numerous respects without departing from the scope of my invention. For example, the water produced by the condensation of the aldehyde with triamine need not necessarily be eliminated from the zone of reaction by means of a constant-boiling mixture with a liquid capable of forming an azeotrope therewith, but on the contrary, such water may be removed satisfactorily by employing a suitable inert dehydrating agent in the reaction mixture. Other modifications and equivalents will be apparent to those skilled in the art, however, it is to be strictly understood that any such modifications or equivalents are to be construed as lying within the scope of my invention.

My invention now having been described, what I claim is:

1. In a process for the synthesis of 1,3,7-triazabicyclo [3.3.0] octanes having the following structure I OH OH wh'erein R is a member selected from the group consisting of hydrogen, alkyl, aryl, cycloaliphatic and heterocyclic radicals; R is a member selected from the group consisting of hydrogen, alkyl, aryl, heterocyclic, cycloaliphatic and aralkyl radicals; and R is a member selected from the group consisting of hydrogen, alkyl, aryl, aralkyl and heterocyclic radicals, the step which comprises reacting an aldehyde with a triamine wherein the amino groups of said triamine are attached to adjacent carbon atoms and having the following general formula wherein the R substituents are as above described.

2. In a process for the synthesis of 1,3,7-triazabicyclo [3.3.0] octanes having the following structure wherein R is a member selected from the group consisting of hydrogen, alkyl, aryl, cycloaliphatic and heterocyclic radicals; R is a member selected from the group consisting of hydrogen, alkyl, aryl, heterocyclic, cycloaliphatic and aralky1 radicals; and R is a member selected from the group consisting of hydrogen, alkyl, aryl, aralkyl and heterocyclic radicals, the step which comprises condensing an aldehyde with a triamine wherein the amino groups of said triamine are attached to adjacent carbon atoms and having the following general formula wherein the R substituents are as above desuch condensation substantially as it is formed.

3. The process of claim 1 in which the aldehyde is formaldehyde.

4. The process of claim 1 in which the aldehyde is benzaldehyde.

5. The process of claim 1 in which the aldehyde is 2-ethylhexaldehyde.

6. In a process for the synthesis of 5-meth'yl- 3,7-diisopropyl-1,3,7-triazabicyclo [3.3.0] octane, the step which comprises condensing formaldehyde with 5-amino-2,5,8-trimethy1-3,7-diazanonane, and removing the water produced by such condensation substantially as it is formed.

7. In a process for the synthesis of 5-methyl- 3,7-diisopropyl-2,8-bis(l-ethylpentyl) 1,3,7 triazabicyclo [3.3.0] octane, the step which comprises condensing. 2-ethylhexaldehyde with 5- amino-2,5,8-trimethyl-3,7-diazanonane, and removing the water produced by such condensation substantially as it is formed.

8. In a process for the synthesis of 5-methyl- 3,7-diphenyl-1,3,7-triazabicyclo [3.3.0] octane, the step which comprises reacting formaldehyde with 2-amino-2-methyl 1,3 propanebisphenylamine, and removing the water produced by such condensation substantially as it is formed.

9. As new compositions of matter, 1,3,7-triazabicyclo [3.3.0] octanes having the following gen eral formula R1 R? on H R1N\/ N -R 11. 5-methyl-3,7-diphenyl-1,3,7 triazabicyclo [3.3.0] octane having the following structure \N N-oni.

CgHrN CH2--( --C 2 12. 5-methyl-3,7-diisopropyl-2,8-bis(1 ethyl pentyl)-1,3,7-triazabicyclo [3.3.0] octane having the following structure CHsCHzCHzCHr- H CHCHzCHzCHaGH;

CH CH:

oH-N N H on, oHr-o-o{ on.

MURRAY SENKUS. 

